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What's the difference between VARCHAR and CHAR?

... CHAR Used to store character string value of fixed length. The maximum no. of characters the data type can hold is 255 characters. It's 50% faster than VARCHAR. Uses static memory allocation. VARCHAR Used to store variable length alphanumeric data. T...
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Set EditText Digits Programmatically

...="fill_parent" android:layout_height="wrap_content" android:hint="@string/ipAddrHint" android:inputType="numberDecimal|number" android:digits="0123456789." android:textSize="30sp" /> share | ...
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Why does String.valueOf(null) throw a NullPointerException?

according to the documentation, the method String.valueOf(Object obj) returns: 4 Answers ...
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Android emulator: How to monitor network traffic?

...o filter out solely emulator traffic, since it is coming from the same src IP. Perhaps the best way would be to set up a very bare VMware environment and only run the emulator in there, at least that way there wouldn't be too much background traffic. ...
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Store boolean value in SQLite

... Which is better in term of performance! true/false as strings or 0/1 integer? – Muhammad Babar Aug 9 '15 at 13:38 ...
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What's the point of malloc(0)?

...ht_be_zero) perhaps could have their uses, although again you have to take extra care not to treat a NULL return as a failure if the value is 0, but a 0 size is supposed to be OK. share | improve th...
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How to convert a string to integer in C?

I am trying to find out if there is an alternative way of converting string to integer in C. 12 Answers ...
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Convert a character digit to the corresponding integer in C

... If, by some crazy coincidence, you want to convert a string of characters to an integer, you can do that too! char *num = "1024"; int val = atoi(num); // atoi = ASCII TO Int val is now 1024. Apparently atoi() is fine, and what I said about it earlier only applies to me (on O...
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Pad a string with leading zeros so it's 3 characters long in SQL Server 2008

I have a string that is up to 3 characters long when it's first created in SQL Server 2008 R2. 17 Answers ...
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Why does Oracle 9i treat an empty string as NULL?

...efore there was a SQL standard, Oracle made the design decision that empty strings in VARCHAR/VARCHAR2 columns were NULL and that there was only one sense of NULL (there are relational theorists that would differentiate between data that has never been prompted for, data where the answer exists but ...